if you'd like, go to the gym twice a week for 20-30 minutes and lift weights separately.
try this routine: leg press, bench press, and row on day 1; overhead press, pull downs (or chin ups, using chin up form on pull downs if you do that), and weighted abdominal exercises (crunches with a weight on your chest, weighted side bends) on day 2.
i did this routine for a month and i leaned out really fast and got great muscle shape. it's an easy, fun routine too. Oh, i do two sets of ten for each exercise.